Hall effect sensors (“Hall sensors”) are used in magnetometers, current sensors and other applications for sensing or detecting magnetic fields. Many Hall sensors employ silicon-based material for transformation of a magnetic field signal into an electrical signal based on galvanomagnetic effects caused by force applied to carriers within the semiconductor material. However, Hall sensors typically suffer from flicker noise, particularly at low frequencies, and generally have a limited minimum detectable magnetic field (MDF). Such low frequency noise effects can be addressed to some extent through various techniques, such as spinning the excitation current through the Hall sensor in orthogonal directions via a switching array, with the sensor output averaged across the four orthogonal directions to cancel offsets and other 1/f noise. However, the spinning current technique (SCT) limits the sensor bandwidth and requires a significant amount of extra circuitry. It is desirable to extend the detectable magnetic field range of Hall sensors without significant bandwidth limitations to allow usage in a variety of applications, while avoiding the area, higher cost and low saturation level shortcomings of other magnetic sensor technology. Graphene Hall sensors (GHS) have been proposed to provide high magnetic field sensitivity, but graphene material has challenges with respect to forming desired low impedance ohmic contacts, and the restrictions on minimum contact resistance may lead to difficulties transferring a Hall sensor signal to amplifiers or other instrumentation circuitry. Moreover, current graphene processing techniques do not ensure repeatable contact resistance values, and variability in contact resistance leads to unpredictable noise performance in many applications. Further, graphene Hall sensors are also subject to flicker and other 1/f noise. Accordingly, use and adoption of graphene Hall sensors has thus far been limited, and the potential benefits associated with graphene material have not been fully achieved.